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1.
J Acoust Soc Am ; 153(4): 2178, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37092912

RESUMEN

Tinnitus is generally considered to be caused by neuroplastic changes in the central nervous system, triggered by a loss of input from the damaged peripheral system; however, conflicting results on auditory brainstem responses (ABRs) to clicks have been reported previously in humans with tinnitus. This study aimed to compare the effect of tinnitus on ABRs to chirps with those to clicks in normal-hearing young adults with tinnitus. The results showed that the tinnitus group had no significantly poorer hearing thresholds (0.25-16 kHz), click-evoked otoacoustic emissions (1-16 kHz), and speech perception in noise (SPIN) than the control group. Although chirps evoked significantly larger wave I and V amplitudes than clicks, people with tinnitus had no significantly smaller wave I amplitudes for either stimulus. Nevertheless, adults with tinnitus exhibited significantly smaller interpeak interval (IPI) between waves I and V for chirps (IPI-chirp) but not for clicks. In addition, the IPI-chirp correlated significantly with the SPIN for individuals with tinnitus when the signal-to-noise ratio was low. The present results suggest that the chirp-evoked ABR may be a valuable clinical tool for objectively assessing the SPIN in individuals with tinnitus. Further studies should be conducted to investigate possible etiologies of tinnitus.


Asunto(s)
Potenciales Evocados Auditivos del Tronco Encefálico , Acúfeno , Humanos , Adulto Joven , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Estimulación Acústica/métodos , Audición/fisiología , Ruido , Umbral Auditivo/fisiología
2.
J Acoust Soc Am ; 141(2): EL115, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28253642

RESUMEN

Reference equivalent threshold sound pressure levels (RETSPLs) are used when calibrating audiometric equipment to a hearing threshold level of zero at various frequencies. To the best of the authors' knowledge, the RETSPLs for Apple EarPods (MB770G) have not been reported, and so this study aimed to measure them. The hearing thresholds of 36 normal-hearing subjects (72 ears) were measured at 250, 500, 1000, 2000, 4000, and 8000 Hz, with the measurements being performed twice in 33 subjects (66 ears) for evaluating the test-retest reliability. This study provides Apple EarPod RETSPLs and shows significant Pearson's correlations (p < 0.001) with no significant Wilcoxon signed-rank test differences (p > 0.01), which confirm the test reliability.

3.
J Am Acad Audiol ; 24(8): 671-83, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24131603

RESUMEN

BACKGROUND: Multichannel wide-dynamic-range compression (WDRC) is a widely adopted amplification scheme in modern digital hearing aids. It attempts to provide individuals with loudness recruitment with superior speech intelligibility and greater listening comfort over a wider range of input levels. However, recent surveys have shown that compression processing (operating in the nonlinear regime) usually reduces the long-term signal-to-noise ratio (SNR). PURPOSE: The purpose of this study was to determine the long-term SNR in an adaptive compression-ratio (CR) amplification scheme called adaptive wide-dynamic-range compression (AWDRC), and to determine whether this concept is better than static WDRC amplification at improving the long-term SNR for speech in noise. DESIGN AND STUDY SAMPLE: AWDRC uses the input short-term dynamic range to adjust the CR to maximize audibility and comfort. Various methods for evaluating the long-term SNR were used to observe the relationship between the CR and output SNR performance in AWDRC for seven typical audiograms, and to compare the results with those for static WDRC amplification. RESULTS: The results showed that the variation of the CR in AWDRC amplification can maintain the comfort and audibility of the output sound. In addition, the average long-term SNR improved by 0.1-5.5 dB for a flat hearing loss, by 0.2-3.4 dB for a reverse sloping hearing loss, by 1.4-4.8 dB for a high-frequency hearing loss, and by 0.3-5.7 dB for a mild-to-moderate-sloping high-frequency hearing loss relative to static WDRC amplification. The output long-term SNR differed significantly (p < .001) between static WDRC and AWDRC amplification. CONCLUSIONS: The results of this study show that AWDRC, which uses the characteristics of the input signal to adaptively adjust the CR, provides better long-term SNR performance than static WDRC amplification.


Asunto(s)
Umbral Auditivo , Audífonos/normas , Pérdida Auditiva de Alta Frecuencia/fisiopatología , Pérdida Auditiva Sensorineural/fisiopatología , Percepción del Habla/fisiología , Diseño de Equipo , Estudios de Seguimiento , Pérdida Auditiva de Alta Frecuencia/rehabilitación , Pérdida Auditiva Sensorineural/rehabilitación , Humanos , Factores de Tiempo
4.
Artículo en Inglés | MEDLINE | ID: mdl-36085875

RESUMEN

Generally, those patients with dysarthria utter a distorted sound and the restrained intelligibility of a speech for both human and machine. To enhance the intelligibility of dysarthric speech, we applied a deep learning-based speech enhancement (SE) system in this task. Conventional SE approaches are used for shrinking noise components from the noise-corrupted input, and thus improve the sound quality and intelligibility simultaneously. In this study, we are focusing on reconstructing the severely distorted signal from the dysarthric speech for improving intelligibility. The proposed SE system prepares a convolutional neural network (CNN) model in the training phase, which is then used to process the dysarthric speech in the testing phase. During training, paired dysarthric-normal speech utterances are required. We adopt a dynamic time warping technique to align the dysarthric-normal utter-ances. The gained training data are used to train a CNN - based SE model. The proposed SE system is evaluated on the Google automatic speech recognition (ASR) system and a subjective listening test. The results showed that the proposed method could notably enhance the recognition performance for more than 10% in each of ASR and human recognitions from the unprocessed dysarthric speech. Clinical Relevance- This study enhances the intelligibility and ASR accuracy from a dysarthria speech to more than 10.


Asunto(s)
Disartria , Habla , Percepción Auditiva , Disartria/diagnóstico , Humanos , Redes Neurales de la Computación , Sonido
5.
J Colloid Interface Sci ; 599: 119-129, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33933786

RESUMEN

Highly transparent leafhopper (Thaia rubiginosa) wings are self-decorated with embroidered ball-shaped proteinaceous brochosmoes as distinct anti-predator defenses. The non-sticky brochosomal coating serves as antireflective structures for camouflage in vegetated environments. Inspired by the leafhopper wings, this study reports a new type of reversible antireflection coating enabled by integrating self-assembly methodologies using a shape memory polymer. The resulting embroidered ball-like structure array establishes a refractive index transition on surface, and thereby behaves omnidirectional antireflective characteristics in a broadband visible light region. Interestingly, the highly transparent appearance can be instantly erased and recovered by submerging in common liquids, such as water and ethanol, or by applying contact pressures at ambient conditions. Furthermore, the reversibility and structure-shape effect on the antireflective characteristics are systematically evaluated in this study.

6.
IEEE Trans Biomed Eng ; 64(11): 2584-2594, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28026747

RESUMEN

Objective: This paper focuses on machine learning based voice conversion (VC) techniques for improving the speech intelligibility of surgical patients who have had parts of their articulators removed. Because of the removal of parts of the articulator, a patient's speech may be distorted and difficult to understand. To overcome this problem, VC methods can be applied to convert the distorted speech such that it is clear and more intelligible. To design an effective VC method, two key points must be considered: 1) the amount of training data may be limited (because speaking for a long time is usually difficult for postoperative patients); 2) rapid conversion is desirable (for better communication). Methods: We propose a novel joint dictionary learning based non-negative matrix factorization (JD-NMF) algorithm. Compared to conventional VC techniques, JD-NMF can perform VC efficiently and effectively with only a small amount of training data. Results: The experimental results demonstrate that the proposed JD-NMF method not only achieves notably higher short-time objective intelligibility (STOI) scores (a standardized objective intelligibility evaluation metric) than those obtained using the original unconverted speech but is also significantly more efficient and effective than a conventional exemplar-based NMF VC method. Conclusion: The proposed JD-NMF method may outperform the state-of-the-art exemplar-based NMF VC method in terms of STOI scores under the desired scenario. Significance: We confirmed the advantages of the proposed joint training criterion for the NMF-based VC. Moreover, we verified that the proposed JD-NMF can effectively improve the speech intelligibility scores of oral surgery patients.Objective: This paper focuses on machine learning based voice conversion (VC) techniques for improving the speech intelligibility of surgical patients who have had parts of their articulators removed. Because of the removal of parts of the articulator, a patient's speech may be distorted and difficult to understand. To overcome this problem, VC methods can be applied to convert the distorted speech such that it is clear and more intelligible. To design an effective VC method, two key points must be considered: 1) the amount of training data may be limited (because speaking for a long time is usually difficult for postoperative patients); 2) rapid conversion is desirable (for better communication). Methods: We propose a novel joint dictionary learning based non-negative matrix factorization (JD-NMF) algorithm. Compared to conventional VC techniques, JD-NMF can perform VC efficiently and effectively with only a small amount of training data. Results: The experimental results demonstrate that the proposed JD-NMF method not only achieves notably higher short-time objective intelligibility (STOI) scores (a standardized objective intelligibility evaluation metric) than those obtained using the original unconverted speech but is also significantly more efficient and effective than a conventional exemplar-based NMF VC method. Conclusion: The proposed JD-NMF method may outperform the state-of-the-art exemplar-based NMF VC method in terms of STOI scores under the desired scenario. Significance: We confirmed the advantages of the proposed joint training criterion for the NMF-based VC. Moreover, we verified that the proposed JD-NMF can effectively improve the speech intelligibility scores of oral surgery patients.


Asunto(s)
Equipos de Comunicación para Personas con Discapacidad , Aprendizaje Automático , Procedimientos Quirúrgicos Orales/efectos adversos , Inteligibilidad del Habla/fisiología , Software de Reconocimiento del Habla , Algoritmos , Humanos , Masculino
7.
PLoS One ; 11(3): e0152028, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27023324

RESUMEN

OBJECTIVES: To determine whether newborn hearing screening in a well-baby nursery (WBN) and neonatal intensive care unit (NICU) nursery: 1) meet three targeted, screening, referral, and diagnostic follow-up rates; 2) compare the average age of diagnosis for infants admitted to the WIN and NICU; and 3) determine prevalence of hearing loss in neonatal population; and 4) try to find a practical newborn hearing screening time algorithm to reduce refer rate in NICU. MATERIALS AND METHODS: It examined 15,624 newborns in the WBN (13,676) and NICU (1948) screened for congenital HL using AABR. The variables analyzed in it were the screening rate, referral rate, follow-up rate, diagnostic rate and diagnostic age, prevalence rate, degrees of congenital bilateral HL. The study was approved by the hospital's institutional review board (13MMHISO23). RESULTS: The screening rates were 99.8% and 99.6% in the WBN and NICU groups, respectively, without significant difference. The referral rates were 0.7% and 2.8% in the WBN and NICU groups, with significant difference. Furthermore, the diagnostic follow-up rates were 76.7% and 89.1% in the WBN and NICU groups, without significant difference. The average initial diagnostic ages were 1.9 months and 3.8 months in the WBN and NICU groups, with significant difference. The prevalence of congenital bilateral hearing loss were 0.27% and 1.6% in the WBN and NICU groups, with significant difference. CONCLUSION: The screening, referral and follow-up rate in the WBN and NICU groups were equivalent to the quality indicators. For NICU group, screening and diagnostic follow up were performed later than those in WBN group; however the lower referral rate in our NICU group was successfully achieved in this study and can be applied clinically. The prevalence of congenital bilateral hearing loss was higher in the NICU group than in the WBN group.


Asunto(s)
Audición/fisiología , Unidades de Cuidado Intensivo Neonatal , Tamizaje Neonatal , Casas Cuna , Derivación y Consulta , Humanos , Recién Nacido , Pacientes Ambulatorios , Alta del Paciente
8.
PLoS One ; 10(3): e0120977, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25835987

RESUMEN

Binaural hearing involves using information relating to the differences between the signals that arrive at the two ears, and it can make it easier to detect and recognize signals in a noisy environment. This phenomenon of binaural hearing is quantified in laboratory studies as the binaural masking-level difference (BMLD). Mandarin is one of the most commonly used languages, but there are no publication values of BMLD or BILD based on Mandarin tones. Therefore, this study investigated the BMLD and BILD of Mandarin tones. The BMLDs of Mandarin tone detection were measured based on the detection threshold differences for the four tones of the voiced vowels /i/ (i.e., /i1/, /i2/, /i3/, and /i4/) and /u/ (i.e., /u1/, /u2/, /u3/, and /u4/) in the presence of speech-spectrum noise when presented interaurally in phase (S0N0) and interaurally in antiphase (SπN0). The BILDs of Mandarin tone recognition in speech-spectrum noise were determined as the differences in the target-to-masker ratio (TMR) required for 50% correct tone recognitions between the S0N0 and SπN0 conditions. The detection thresholds for the four tones of /i/ and /u/ differed significantly (p<0.001) between the S0N0 and SπN0 conditions. The average detection thresholds of Mandarin tones were all lower in the SπN0 condition than in the S0N0 condition, and the BMLDs ranged from 7.3 to 11.5 dB. The TMR for 50% correct Mandarin tone recognitions differed significantly (p<0.001) between the S0N0 and SπN0 conditions, at -13.4 and -18.0 dB, respectively, with a mean BILD of 4.6 dB. The study showed that the thresholds of Mandarin tone detection and recognition in the presence of speech-spectrum noise are improved when phase inversion is applied to the target speech. The average BILDs of Mandarin tones are smaller than the average BMLDs of Mandarin tones.


Asunto(s)
Enmascaramiento Perceptual , Inteligibilidad del Habla , Habla , Adolescente , Adulto , Audiometría de Tonos Puros , Femenino , Humanos , Masculino , Adulto Joven
9.
PLoS One ; 9(6): e98925, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24901647

RESUMEN

BACKGROUND AND AIMS: Arsenic trioxide (As2O3), which used as an effective agent in the treatment of leukaemia and other solid tumors, is largely limited by its toxicity. QT prolongation, torsades de pointes and sudden heart death have been implicated in the cardiotoxicity of As2O3. The present study was designed to explore whether the combination of As2O3 and resveratrol could generate a more powerful anti-cancer effect both in vitro and in vivo. MATERIALS AND METHODS: MTT assay was performed to assess the proliferation of Hela, MCF-7 and NB4 cells. Isobolographic analysis was used to evaluate combination index values from cell viability data. The apoptosis and the cellular reactive oxygen species (ROS) level were assessed by fluorescent microscopy and flow cytometry separately in vitro. The effect of As2O3, alone and in combination with resveratrol on Hela tumor growth in an orthotopic nude mouse model was also investigated. The tumor volume and the immunohistochemical analysis of CD31, CD34 and VEGF were determined. RESULTS: Resveratrol dramatically enhanced the anti-cancer effect induced by As2O3 in vitro. In addition, isobolographic analysis further demonstrated that As2O3 and resveratrol generated a synergistic action. More apoptosis and ROS generation were observed in the combination treatment group. Similar synergistic effects were found in nude mice in vivo. The combination of As2O3 and resveratrol dramatically suppressed both tumor growth and angiogenesis in nude mice. CONCLUSIONS: Combining As2O3 with resveratrol would be a novel strategy to treat cancer in clinical practice.


Asunto(s)
Antineoplásicos/farmacología , Arsenicales/farmacología , Óxidos/farmacología , Estilbenos/farmacología , Animales , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Trióxido de Arsénico , Arsenicales/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Humanos , Masculino , Ratones , Necrosis/tratamiento farmacológico , Necrosis/patología , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Óxidos/administración & dosificación , Especies Reactivas de Oxígeno/metabolismo , Resveratrol , Estilbenos/administración & dosificación , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
10.
PLoS One ; 8(11): e80831, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24278326

RESUMEN

OBJECTIVE: The purpose of this study was to design and to verify a new hearing-aid fitting strategy (Aescu HRL-1) based on the acoustic features of Mandarin. The subjective and objective outcomes were compared to those fitted with NAL-NL1 (National Acoustic Laboratory Non-Linear, version1) in Mandarin-speaking hearing-aid users. DESIGN: Fifteen subjects with sensorineural hearing loss participated in this preliminary study. Each subject wore a pair of four-channel hearing aids fitted with the Aescu HRL-1 and NAL-NL1 prescriptions alternatively for 1 month. Objective and subjective tests including the Mandarin Monosyllable Recognition Test (MMRT), Mandarin Hearing in Noise Test (MHINT), International Outcome Inventory for Hearing Aids (IOI-HA), and a sound-quality questionnaire were used to evaluate the performance of the two prescriptions. RESULTS: The mean MMRT scores were 79.9% and 81.1% for NAL-NL1 and Aescu HRL-1 respectively. They are not statistically different. The corresponding MHINT signal-to-noise ratios were 0.87 and 0.85 dB, also, no significant difference was found between these two strategies. However, in subjective questionnaires, overall, the sound-quality and IOI-HA scores were higher for Aescu HRL-1. CONCLUSIONS: The speech recognition performance based on Aescu HRL-1 is as good as that of NAL-NL1 for Mandarin-speaking hearing-aid users. Moreover, the subjects generally responded that Aescu HRL-1 provides a more natural, richer, and better sound quality than does NAL-NL1.


Asunto(s)
Audífonos , Lenguaje , Adulto , Anciano , Umbral Auditivo/fisiología , Femenino , Humanos , Percepción Sonora/fisiología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Relación Señal-Ruido , Sonido , Encuestas y Cuestionarios , Adulto Joven
11.
Integr Cancer Ther ; 10(4): 312-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21382955

RESUMEN

Anthracyclines are potent antineoplastic agents associated with cardiotoxicity, which may lead to congestive heart failure, causing impairment of autonomic cardiovascular function as assessed by heart rate variability (HRV). This decreases survival rates. This study aimed to determine whether music therapy intervention improves autonomic function in anthracycline-treated breast cancer patients, and if so, whether such improvements persist after cessation of the intervention. Participants were 12 women with breast cancer who had undergone mastectomy or breast-conserving treatment and adjuvant chemotherapy; they attended 8 weekly music therapy sessions, each lasting 2 hours. Electrocardiogram traces (5 minutes) for HRV analysis were recorded 4 times: prior to the first music session, T1; after the fourth music session, T2; after the eighth music session, T3; and 4 weeks after the completion of music therapy, T4. HRV parameters were subjected to a nonparametric Friedman test on the differences between T1 and T2, T3, and T4. The standard deviation of normal intervals and the total power of HRV parameters, related to global autonomic function, were significantly higher at T3 than at T1. The root-mean-square differences of successive normal R-R intervals and high-frequency (HF) HRV parameters, related to parasympathetic activity, were significantly increased, but no change was seen in the LF/HF ratio of HRV parameters (which is related to sympathetic activity) during the music therapy. Global autonomic function and parasympathetic activity had not changed significantly at T4 relative to T1. The authors provide preliminary evidence of the benefits of music therapy for anthracycline-treated breast cancer survivors.


Asunto(s)
Antibióticos Antineoplásicos/efectos adversos , Sistema Nervioso Autónomo/fisiopatología , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/efectos adversos , Cardiopatías/terapia , Musicoterapia , Adulto , Antibióticos Antineoplásicos/uso terapéutico , Sistema Nervioso Autónomo/efectos de los fármacos , Neoplasias de la Mama/fisiopatología , Cardiotoxinas/efectos adversos , Cardiotoxinas/uso terapéutico , Doxorrubicina/uso terapéutico , Electrocardiografía , Femenino , Cardiopatías/inducido químicamente , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad
12.
Complement Ther Med ; 18(5): 224-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21056846

RESUMEN

OBJECTIVE: Data on the effects of music therapy on subjective sensations and the physiological parameters of heart rate variability (HRV) in treated cancer survivors are scarce. The aim of this study was to determine whether or not music therapy affects the sensations of fatigue, comfort, and relaxation in cancer survivors, and affects the activities of the sympathetic and parasympathetic nervous systems as indicated by HRV parameters. METHODS: Twenty-three patients aged 30-67 years and with cancer that had been treated at least 6 months previously received music therapy for about 2h, which included singing, listening to music, learning the recorder, and performing music. Subjective sensations and electrocardiogram were recorded before and after the music therapy. The low-frequency and high-frequency components of HRV were assessed by the frequency analysis of sequential R wave to R wave intervals of electrocardiogram obtained from 5-min recordings. Subjective sensations were quantitatively assessed using a visual analog mood scale. RESULTS: Two hours of music therapy significantly increased relaxation sensations and significantly decreased fatigue sensation in treated cancer survivors. Moreover, the HRV parameters showed that parasympathetic nervous system activity increased and sympathetic nervous system activity decreased. CONCLUSION: This study provides preliminary evidence that music therapy may be clinically useful for promoting relaxation sensation and increasing parasympathetic nervous system activity in treated cancer survivors.


Asunto(s)
Fatiga , Frecuencia Cardíaca/fisiología , Musicoterapia , Neoplasias/fisiopatología , Sistema Nervioso Parasimpático/fisiología , Sistema Nervioso Simpático/fisiología , Adulto , Afecto , Anciano , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Dimensión del Dolor , Proyectos Piloto , Relajación , Sensación
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